Our greatest threats, worries, and fears no longer reside in our external environment but within the depths of our own consciousness. When our mind wanders, it slips into a pattern of ruminating on the stupid things we’ve said, the arguments we’ve won and lost, and worries about work and money. This is also true of pleasurable thoughts—we daydream of memorable meals, recall memories from a great vacation, or fantasize about how great we’d feel if we had come up with a witty retort to something said earlier.
